/*
 * Copyleft 2010 Mustafa DUMLUPINAR
 *
 * Distributable under LGPL license.
 * See terms of license at gnu.org.
 * http://www.gnu.org/licenses/lgpl.html
 *
 * dumlupinar01@gmail.com
 * http://mdpinar.blogspot.com/
 *
 */
package com.gmvc.client.util;

/**
 * Kullanici sifre dogrulugunu kontrol etmek icin bu sinif kullanilir. 
 * 
 * <p/>
 * Benzer bir yapi server tarafinda da java kodlari ile yazildi, burdaki native 
 * javascript kodlaridir. 
 * 
 * @author mdpinar
 * 
 */
public final class Hash {

	/**
	 * Ornegi alinamaz
	 */
	private Hash() {
		;
	}

	/**
	 * Verilen duz string veriyi md5 dizesine cevirir, sifre denetiminde kullaniliyor
	 *  
	 * @param data duz string data
	 * @return md5 dizesine cevrilmis data
	 * 
	 */
	public static native String md5(String data) /*-{ 
		function RotateLeft(lValue, iShiftBits) {
			return (lValue<<iShiftBits) | (lValue>>>(32-iShiftBits));
		}
	 
		function AddUnsigned(lX,lY) {
			var lX4,lY4,lX8,lY8,lResult;
			lX8 = (lX & 0x80000000);
			lY8 = (lY & 0x80000000);
			lX4 = (lX & 0x40000000);
			lY4 = (lY & 0x40000000);
			lResult = (lX & 0x3FFFFFFF)+(lY & 0x3FFFFFFF);
			if (lX4 & lY4) {
				return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
			}
			if (lX4 | lY4) {
				if (lResult & 0x40000000) {
					return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
				} else {
					return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
				}
			} else {
				return (lResult ^ lX8 ^ lY8);
			}
	 	}
	 
	 	function F(x,y,z) { return (x & y) | ((~x) & z); }
	 	function G(x,y,z) { return (x & z) | (y & (~z)); }
	 	function H(x,y,z) { return (x ^ y ^ z); }
		function I(x,y,z) { return (y ^ (x | (~z))); }
	 
		function FF(a,b,c,d,x,s,ac) {
			a = AddUnsigned(a, AddUnsigned(AddUnsigned(F(b, c, d), x), ac));
			return AddUnsigned(RotateLeft(a, s), b);
		};
	 
		function GG(a,b,c,d,x,s,ac) {
			a = AddUnsigned(a, AddUnsigned(AddUnsigned(G(b, c, d), x), ac));
			return AddUnsigned(RotateLeft(a, s), b);
		};
	 
		function HH(a,b,c,d,x,s,ac) {
			a = AddUnsigned(a, AddUnsigned(AddUnsigned(H(b, c, d), x), ac));
			return AddUnsigned(RotateLeft(a, s), b);
		};
	 
		function II(a,b,c,d,x,s,ac) {
			a = AddUnsigned(a, AddUnsigned(AddUnsigned(I(b, c, d), x), ac));
			return AddUnsigned(RotateLeft(a, s), b);
		};
	 
		function ConvertToWordArray(data) {
			var lWordCount;
			var lMessageLength = data.length;
			var lNumberOfWords_temp1=lMessageLength + 8;
			var lNumberOfWords_temp2=(lNumberOfWords_temp1-(lNumberOfWords_temp1 % 64))/64;
			var lNumberOfWords = (lNumberOfWords_temp2+1)*16;
			var lWordArray=Array(lNumberOfWords-1);
			var lBytePosition = 0;
			var lByteCount = 0;
			while ( lByteCount < lMessageLength ) {
				lWordCount = (lByteCount-(lByteCount % 4))/4;
				lBytePosition = (lByteCount % 4)*8;
				lWordArray[lWordCount] = (lWordArray[lWordCount] | (data.charCodeAt(lByteCount)<<lBytePosition));
				lByteCount++;
			}
			lWordCount = (lByteCount-(lByteCount % 4))/4;
			lBytePosition = (lByteCount % 4)*8;
			lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80<<lBytePosition);
			lWordArray[lNumberOfWords-2] = lMessageLength<<3;
			lWordArray[lNumberOfWords-1] = lMessageLength>>>29;
			return lWordArray;
		};
	 
		function WordToHex(lValue) {
			var WordToHexValue="",WordToHexValue_temp="",lByte,lCount;
			for (lCount = 0;lCount<=3;lCount++) {
				lByte = (lValue>>>(lCount*8)) & 255;
				WordToHexValue_temp = "0" + lByte.toString(16);
				WordToHexValue = WordToHexValue + WordToHexValue_temp.substr(WordToHexValue_temp.length-2,2);
			}
			return WordToHexValue;
		};
	 
		function Utf8Encode(data) {
			data = data.replace(/\r\n/g,"\n");
			var utftext = "";
	 
			for (var n = 0; n < data.length; n++) {
	 
				var c = data.charCodeAt(n);
	 
				if (c < 128) {
					utftext += String.fromCharCode(c);
				}
				else if((c > 127) && (c < 2048)) {
					utftext += String.fromCharCode((c >> 6) | 192);
					utftext += String.fromCharCode((c & 63) | 128);
				}
				else {
					utftext += String.fromCharCode((c >> 12) | 224);
					utftext += String.fromCharCode(((c >> 6) & 63) | 128);
					utftext += String.fromCharCode((c & 63) | 128);
				}
	 
			}
	 
			return utftext;
		};
	 
		var x=Array();
		var k,AA,BB,CC,DD,a,b,c,d;
		var S11=7, S12=12, S13=17, S14=22;
		var S21=5, S22=9 , S23=14, S24=20;
		var S31=4, S32=11, S33=16, S34=23;
		var S41=6, S42=10, S43=15, S44=21;
	 
		data = Utf8Encode(data);
	 
		x = ConvertToWordArray(data);
	 
		a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
	 
		for (k=0;k<x.length;k+=16) {
			AA=a; BB=b; CC=c; DD=d;
			a=FF(a,b,c,d,x[k+0], S11,0xD76AA478);
			d=FF(d,a,b,c,x[k+1], S12,0xE8C7B756);
			c=FF(c,d,a,b,x[k+2], S13,0x242070DB);
			b=FF(b,c,d,a,x[k+3], S14,0xC1BDCEEE);
			a=FF(a,b,c,d,x[k+4], S11,0xF57C0FAF);
			d=FF(d,a,b,c,x[k+5], S12,0x4787C62A);
			c=FF(c,d,a,b,x[k+6], S13,0xA8304613);
			b=FF(b,c,d,a,x[k+7], S14,0xFD469501);
			a=FF(a,b,c,d,x[k+8], S11,0x698098D8);
			d=FF(d,a,b,c,x[k+9], S12,0x8B44F7AF);
			c=FF(c,d,a,b,x[k+10],S13,0xFFFF5BB1);
			b=FF(b,c,d,a,x[k+11],S14,0x895CD7BE);
			a=FF(a,b,c,d,x[k+12],S11,0x6B901122);
			d=FF(d,a,b,c,x[k+13],S12,0xFD987193);
			c=FF(c,d,a,b,x[k+14],S13,0xA679438E);
			b=FF(b,c,d,a,x[k+15],S14,0x49B40821);
			a=GG(a,b,c,d,x[k+1], S21,0xF61E2562);
			d=GG(d,a,b,c,x[k+6], S22,0xC040B340);
			c=GG(c,d,a,b,x[k+11],S23,0x265E5A51);
			b=GG(b,c,d,a,x[k+0], S24,0xE9B6C7AA);
			a=GG(a,b,c,d,x[k+5], S21,0xD62F105D);
			d=GG(d,a,b,c,x[k+10],S22,0x2441453);
			c=GG(c,d,a,b,x[k+15],S23,0xD8A1E681);
			b=GG(b,c,d,a,x[k+4], S24,0xE7D3FBC8);
			a=GG(a,b,c,d,x[k+9], S21,0x21E1CDE6);
			d=GG(d,a,b,c,x[k+14],S22,0xC33707D6);
			c=GG(c,d,a,b,x[k+3], S23,0xF4D50D87);
			b=GG(b,c,d,a,x[k+8], S24,0x455A14ED);
			a=GG(a,b,c,d,x[k+13],S21,0xA9E3E905);
			d=GG(d,a,b,c,x[k+2], S22,0xFCEFA3F8);
			c=GG(c,d,a,b,x[k+7], S23,0x676F02D9);
			b=GG(b,c,d,a,x[k+12],S24,0x8D2A4C8A);
			a=HH(a,b,c,d,x[k+5], S31,0xFFFA3942);
			d=HH(d,a,b,c,x[k+8], S32,0x8771F681);
			c=HH(c,d,a,b,x[k+11],S33,0x6D9D6122);
			b=HH(b,c,d,a,x[k+14],S34,0xFDE5380C);
			a=HH(a,b,c,d,x[k+1], S31,0xA4BEEA44);
			d=HH(d,a,b,c,x[k+4], S32,0x4BDECFA9);
			c=HH(c,d,a,b,x[k+7], S33,0xF6BB4B60);
			b=HH(b,c,d,a,x[k+10],S34,0xBEBFBC70);
			a=HH(a,b,c,d,x[k+13],S31,0x289B7EC6);
			d=HH(d,a,b,c,x[k+0], S32,0xEAA127FA);
			c=HH(c,d,a,b,x[k+3], S33,0xD4EF3085);
			b=HH(b,c,d,a,x[k+6], S34,0x4881D05);
			a=HH(a,b,c,d,x[k+9], S31,0xD9D4D039);
			d=HH(d,a,b,c,x[k+12],S32,0xE6DB99E5);
			c=HH(c,d,a,b,x[k+15],S33,0x1FA27CF8);
			b=HH(b,c,d,a,x[k+2], S34,0xC4AC5665);
			a=II(a,b,c,d,x[k+0], S41,0xF4292244);
			d=II(d,a,b,c,x[k+7], S42,0x432AFF97);
			c=II(c,d,a,b,x[k+14],S43,0xAB9423A7);
			b=II(b,c,d,a,x[k+5], S44,0xFC93A039);
			a=II(a,b,c,d,x[k+12],S41,0x655B59C3);
			d=II(d,a,b,c,x[k+3], S42,0x8F0CCC92);
			c=II(c,d,a,b,x[k+10],S43,0xFFEFF47D);
			b=II(b,c,d,a,x[k+1], S44,0x85845DD1);
			a=II(a,b,c,d,x[k+8], S41,0x6FA87E4F);
			d=II(d,a,b,c,x[k+15],S42,0xFE2CE6E0);
			c=II(c,d,a,b,x[k+6], S43,0xA3014314);
			b=II(b,c,d,a,x[k+13],S44,0x4E0811A1);
			a=II(a,b,c,d,x[k+4], S41,0xF7537E82);
			d=II(d,a,b,c,x[k+11],S42,0xBD3AF235);
			c=II(c,d,a,b,x[k+2], S43,0x2AD7D2BB);
			b=II(b,c,d,a,x[k+9], S44,0xEB86D391);
			a=AddUnsigned(a,AA);
			b=AddUnsigned(b,BB);
			c=AddUnsigned(c,CC);
			d=AddUnsigned(d,DD);
		}
	 
		var temp = WordToHex(a)+WordToHex(b)+WordToHex(c)+WordToHex(d);
	 
		return temp.toLowerCase();
	}-*/;

}
